Technology represents the discovery, improvement, and implementation of new tools, techniques, and customs that give a wide variety of powerful bonuses across every field. Technologically advanced nations will field a more effective military, make more efficient use of their pops and resources, and be able to create a more stable and loyal realm, while those that fall behind will find it increasingly difficult to keep up with their peers. All technologies fall into one of four fields - martial, civic, oratory and religious - and can be divided between generic advances that gain progress from generation of research points by nobles and citizens, and the more specific inventions that can be adopted by spending the innovations that advances grant. The main technology interface can be accessed though the technology tab in the side menu bar.
Advances represent the general level of knowledge and technology that the country has reached. They provide a baseline level of modifiers from increased technology and each advance grants 1 innovation that can be used to unlock an invention. There is no cap in the maximum level of advances that can be achieved, though ahead-of-time penalties will effectively give a soft cap to the level of advances that is realistically possible to achieve. Advances are slowly researched over time based on the amount of research points that a country produces in proportion to its integrated culture population, subject to many different modifiers that can further increase or decrease the speed at which research progress is accumulated.
Starting advances level
Each country starts with a predetermined level of technological advances, usually determined by their culture and civilization level, along with a number of unused innovations corresponding to its starting advances level (if applicable).
- Italic culture group (except Ligurian, Venetic, and Rhaetian)
- Hellenistic culture group (except Cappadocia and Parthia)
- Lycian culture
- Bithynian culture
- Punic and Phoenician culture
- Assyrian and Babylonian culture
- Median culture
- Tamil culture (if coastal)
- Magadhi, Shauraseni, Gandhari, Avanti, and Lankan culture
- Bactrian culture group
- Meroitic culture (except Boras)
- Aksumite culture group
- Ligurian culture (except Oxybia)
- Aramaic culture
- Hebrew culture
- Colchian and Ibero culture
- Armenian culture
- Tamil culture (if inland)
All other countries start with no advances (level 0) or innovations.
Research points represent the contribution of pops towards the technological and intellectual advancement of the country, and are summed up over every pop in every owned territory every month to get the total research points for the state. Research points are generated exclusively by nobles and citizens, who produce a base output of 0.5 and 0.2 research points, respectively, each month at 100% happiness. Therefore, research point production is also affected by noble output and citizen output as well as research point modifiers, and is also heavily dependent on the proportion and happiness of nobles and citizens in the country. This means that in addition to directly maximizing research point production (such as by building libraries and increasing overall population output with foundries and raising civilization level), increasing noble ratio and citizen ratio directly through laws and academies and courts of law or indirectly by building more and larger cities (as nobles and citizens do not exist in appreciable numbers in settlements) are also an effective longer-term solution towards increasing research point production. Large cities and metropolises are usually the largest source of research points in the middle to late game, as the stacking effects of academies and courts of law as well as general civilization level increases from buildings means that they usually have both the highest proportion of nobles and citizens and the highest happiness and research point production per noble/citizen, though population capacity means that larger empires will still need a significant number of cities to produce enough research.
The following inventions give percentage increases to the amount of research points produced:
- +10% from Scientific Patronage ( Oratory inventions, requires regional power status)
- +10% from Sponsored Research ( Oratory inventions, requires major power status)
- +5% from Stoicism ( Civic inventions, requires Hellenistic primary or integrated culture)
- +5% from Hindu Number System ( Oratory inventions, requires Aryan, Dravidan or Pracyan primary or integrated culture)
- +5% from Trigonometry ( Oratory inventions, requires Aryan, Dravidan or Pracyan primary or integrated culture)
Monthly research is the base value of research progress for all four fields and is obtained by dividing research efficiency by 192, corresponding to a base time of 192 months (16 years) for each advance. The baseline research efficiency cap of 125% initially caps monthly research at 0.65%, with the maximum possible research efficiency of 250% giving a highest possible base monthly research of 1.30%.
Research progress is the actual monthly progress in each field of advances. The base value is the monthly research, which is then modified by the field-specific research speed modifier. The technology speed modifier affects the research speed in all fields, while the field-specific technology modifiers ( military tech investment, civic tech investment, oratory tech investment, and religious tech investment) are applied only to the research speed of one specific field. Modifiers to research speed can come from various deity bonuses and omens, country heritages, trade goods, and event/mission modifiers, but the main component of research speed for each field will typically be the attribute of the field's researcher corresponding to the field. The behind/ahead of time modifier is applied multiplicatively after all the other modifiers, and gives a -0.75% malus for each year ahead and +0.75% bonus for each year behind the country is compared to the benchmark of 1 advance every 16 years after the start of the game. Certain events can also directly increase the amount of research progress accumulated in a particular field.
An advance will be researched once the total research progress for that field reaches 100%, with any overflow carried over for the next advance. The progress and effects (including unlocked inventions) of the next advance in each field can be viewed in the tooltip of the corresponding progress bar.
Research efficiency is the ratio of research points produced per year to integrated culture population and the main component of the actual research progress each month, meaning that larger countries generally need higher research point generation in order to keep up with research. It is calculated according to the following formula:
Generally, it is desirable to keep research efficiency at at least 80% in order to research advances at a reasonable pace. Research efficiency has a baseline cap of 125%, modified by the maximum research efficiency modifier. Each of the following inventions gives +25% maximum research efficiency, giving a maximum of 250% research efficiency if all of them are adopted:
- Embracing Philosophy ( Civic inventions)
- Stoicism ( Civic Invention, requires Hellenistic primary or integrated culture)
- Book Binding ( Oratory inventions)
- Theological Colleges ( Religious inventions)
- Scribae ( Religious Invention)
Even though research efficiency is capped, it can still be useful to try to push the research points to population ratio higher in order to provide a buffer when assimilating pops or integrating new territory. Small, highly urbanized city-states will generally have a much higher research efficiency than sprawling empires with many rural pops, though it is possible to have a high research efficiency even with the largest empires so long as the major cities are sufficiently large and research-focused, of which growth through enslavement, migration, and continued urbanization will typically be needed to keep up.
As the denominator of research efficiency is based on the integrated culture population, not the total population, it is also possible to get high research efficiency by keeping a relatively small core of integrated culture pops compared to the empire's total output - especially useful is conquering foreign areas with significant numbers of nobles and citizens, as they will produce research points but not count against the denominator for research efficiency. However, the lower happiness of unintegrated culture pops, and particularly those of the higher classes that produce research, generally means that more care has to be taken to ensure their happiness and keep unrest under control compared to integrating them.
Each technology field can have one researcher assigned to it, who leads the research efforts in that field and has a significant influence on how quickly advances in that field progress, giving a +10% research speed boost for each attribute point corresponding to the field ( martial for military advances, finesse for civic advances, charisma for oratory advances, and zeal for religious advances). Like all other jobs and offices, holding the researcher position counts towards prominence, family prestige, power base, and the number of positions that a major family expects to hold.
The modifiers for a single level of advances in each field are listed below. Each level provides an additional modifier on top of the previous ones already accumulated.
- +0.075 Morale of Armies
- +0.075 Morale of Navies
- +2.5% Legion Maintenance Cost
- +2.5% Navy Maintenance Cost
- Main article: Invention
Inventions represent specific technologies or practices that can be adopted by the state in order to get a specific military, economic, or political effects and bonuses. Every invention is associated with a specific field of advances and is structured as part of a tree, with most inventions requiring prerequisites that must be adopted first before the next invention can be taken. Inventions are adopted by spending innovations, gained primarily from technological advances (which grant one innovation for each level) as well as from a few military traditions, mission tasks, and events.