Technology is the practical application of knowledge, in processes, methods, or organization. In EU2, technology is extremely important, but nonetheless relatively simple. There are only four technologies: land tech, naval tech, trade tech, and infrastructure tech. Each country has its own level in each of the four, largely independent of other countries'. Tech levels are just numbers, from 0 to 10 for the economic technologies (trade and infrastructure), and from 0 to 60 for the military technologies (land and naval).
In addition to tech levels, each country also has an "investment account" for each technology, which represents how much investment it has made towards the next level in that tech. These accounts are denominated in ducats. See the article on income for information on how they are filled. The price of the next level of technology is discussed below.
There are no general effects of technology; the effect of progress in each particular field is listed in its own specific article:
The cost of the next level in a particular field of technology is its technology cost. To see the tech cost for a particular field, mouse over its slider on the budget screen; the tech cost is shown on the tooltip.
The computation of tech cost is rather complex. There is a base cost for each level, which can be looked up in the tech table for each particular tech. Technology cost is the base cost times six factors, one of which is composed of 6 addends. These are summarized as follows:
tech_cost(C,T,N) = base_cost(T,N) * ahead_of_time_factor(T,N) * techgroup_factor(C) * domestic_policy_factor(C) * defender_of_the_faith_factor(C) * tech_speed_factor(C) * inflation(C)
- C is the country.
- T is the tech type (land/naval/infra/trade)
- N is the next tech level (i.e., if C currently has land 9, N is 10).
There is no rounding in the computation, but the displayed value is truncated.
The base cost for each tech level is listed in each tech table.
Ahead of Time Factor
This factor penalizes research that is finished "too soon"; it is basically a play-balance hack to prevent countries from teching much faster than they did historically. It is computed as follows:
ahead_of_time_factor(T,N) = 1.0, if (current_year >= ahead_of_time_date(T,N)) = 1.5 + (ahead_of_time_date(T,N) - current_year)*0.1
The ahead of time date (ATD) for each tech level is listed in each tech table.
For modders, here is how ATD is computed: for a given level N, you look up the level N-2 in the tech's .csv file (i.e. land.csv for land tech). Then you subtract five from the field given as "Average Date for Next" in that file.
Tech Group Factor
The techgroup factor is a hard-coded factor based on the techgroup a country is in.
Techgroup techgroup_factor latin 1.0 orthodox 1.1 muslim 1.2 china 1.4 exotic 1.9
Domestic Policy Factor
Two of the domestic policy sliders affect tech costs: centralization and innovative. Centralization gives a bonus or malus of up to 10% to tech costs; innovate, 15%. These effects are summarized here, given in percentages, for each of the 11 positions of each slider:
0 1 2 3 4  6 7 8 9 10 Centralization +10 +8 +6 +4 +2 0 -2 -4 -6 -8 -10 Innovation +15 +12 +9 +6 +3 0 -3 -6 -9 -12 -15
The domestic_policy_factor is the sum of 1.0, and the two percentages above. For example, a country has centralization 1 and innovative 6. Its domestic_policy_factor is 1.0 + .08 - .03 = 1.05.
Defender of Faith Factor
If a country hold the title of Defender of the Faith, its tech is somewhat more expensive:
defender_of_the_faith_factor(C) = 1.15, if the country C is defender of its faith
defender_of_the_faith_factor(C) = 1.0
Tech Speed Multiplier
The tech speed factor is a composite factor, which is computed by adding up six addends based on various attributes of the country. The following equation summarizes this, and is appropriate for most countries:
tech_speed_factor(C) = #cities_addend(C) + religion_added(C) + vassals_addend(C) + HRE_addend(C) + isolation_addend(C) + whiteman_addend(C)
However, there are two limits not shown in the formula as it is above. The sum of the addends for #cities, religion, vassals and HRE cannot be greater than 4.0, if it is, 4.0 is substituted. Also, the total tech_speed_factor can't be less than 1.0; if it is, then 1.0 is substituted. Thus, we can more correctly write this:
tech_speed_factor(C) = maximum(1.0, minimum(4.0, #cities_addend(C) + religion_factor(C) + vassal_addend(C) + HRE_addend(C)) + isolation_addend(C) + whiteman_addend(C))
It's harder to read and make sense of.
The number of cities addend for a country is based on how many cities it owns. Cities does not include colonies and trading posts.
#cities #cities_addend 1 1.0 2 1.2 3 1.4 4 1.5 5 1.6 6 1.8 7 1.9 8 2.0 9+ 2.0 + 0.025 per city over 8
The religion addend to the tech_speed_factor is determined by a country's state religion:
religion religion_addend Reformed -0.04 Protestant -0.02 Catholic +0.02 Orthodox +0.02 Sunni +0.02 CrC +0.06 Shiite +0.06 Buddhist +0.10 Confucian +0.20 Hindu +0.20 Pagan +0.50
A country with one or more vassals may get a tiny reduction to tech costs, no more than -0.02. (Whoopee!) This depends on the country's centralization domestic policy, and the continental location of the vassal(s) relative to the country:
vassal_addend Centralization Same Different Setting Continent Continent 0-5 -0.02 -0.02 6 -0.02 -0.016 7 -0.02 -0.012 8 -0.016 -0.008 9 -0.008 -0.004 10 0 0
Having more vassals can increase the modifier, but only if they are all on the same continent as the suzerein, and always capped at -0.02. Thus, having 2+ vassals will only have an effect with cent 8 or 9.
The country that is the emperor of the Holy Roman Empire, gets -0.02 added per supportive elector other than itself.
The isolation addend, also called the isolation penalty, ranges up to 4.8, and applies to any country which knows less than 19 other countries.
This only applies to countries on the American continent. It is based on a country's whiteman value; see the linked article for discussion.
whiteman whiteman_addend 0 10 1 8 2 6 3 4 4 2 5+ 0