The tech tree Techs (short for "technologies") are empire upgrades that cost science and provide various benefits and make additional techs and some laws and events available.
Tier 1 (80 Science)
Technology
Prerequisites
Leads To
Effects
Ironworking
None
Warrior
Stonecutting
None
Fort, Quarry
Trapping
None
Slinger, Camp
Divination
None
Shrine
Administration
None
Rhetoric, Free Worker
Treasury, Granary
Tier 2 (120 Science)
Technology
Prerequisites
Leads To
Effects
Labor Force
Ironworking
Husbandry
Ironworking
Drama
Stonecutting
Polis
Stonecutting, Trapping
Military Drill
Trapping
Aristocracy
Divination
Border Boost, Sovereignty (with Rhetoric), Monasticism
Ambassador, Centralization / Vassalage
Rhetoric
Administration
Border Boost - All Cities +6 Border Tiles
Tier 3 (200 Science)
Technology
Prerequisites
Leads To
Effects
Navigation
Labor Force
Phalanx
Labor Force
Spoked Wheel
Husbandry
Forestry
Polis
Steel
Military Drill, Ironworking
Sovereignty
Aristocracy, Rhetoric
Metaphysics
Rhetoric
Tier 4 (400 Science)
Technology
Prerequisites
Leads To
Effects
Coinage
Navigation
Money Boost, Lateen Sail (with Cartography)
Market, Pacify City, Automate Workers
Citizenship
Phalanx
Scholarship, Stirrups (with Spoked Wheel), Free Court Minister
Courthouse, Divine Rule / Legal Code
Portcullis
Drama
Land Consolidation
Forestry
Composite Bow
Military Drill
Manor (with Land Consolidation), Free Akkadian Archer, Free Archer, Free Palton Cavalry
Archer, Range
Monasticism
Aristocracy
Machinery
Sovereignty
Tier 5 (600 Science)
Technology
Prerequisites
Leads To
Effects
Scholarship
Citizenship
Stirrups
Spoked Wheel, Citizenship
Architecture
Portcullis
Vaulting, Free Siege Tower
Bath, Philosophy / Engineering
Manor
Land Consolidation, Composite Bow
Battle Line
Steel, Phalanax
Barding (with Martial Code), Cohorts (with Land Consolidation), Free Court Soldier
Maceman
Doctrine
Monasticism
Torsion
Machinery
Cartography
Metaphysics, Navigation
Lateen Sail (with Coinage), Ballistics (with Hydraulics)
Trireme, Harbor, Steal Research
Tier 6 (800 Science)
Technology
Prerequisites
Leads To
Effects
Hydraulics
Coinage
Jurisprudence
Scholarship
Martial Code
Stirrups
Vaulting
Architecture
Bodkin Arrow
Manor
Infantry Square, Free Longbowman, Free Cimmerian Archer
Longbowman
Cohorts
Land Consolidation, Battle Line
Military Prestige (with Barding and Infantry Square), Free Legionary
Swordsman
Windlass
Torsion
Tier 7 (1000 Science)
Technology
Prerequisites
Leads To
Effects
Lateen Sail
Hydraulics
Fiscal Policy
Jurisprudence
Barding
Steel, Martial Code
Military Prestige (with Infantry Square and Cohorts)
Cataphract
Infantry Square
Bodkin Arrow
Chain Drive
Windlass
Industrial Progress (with Ballistics)
Polybolos
Ballistics
Hydraulics, Cartography
Industrial Progress (with Chain Drive)
Mangonel
Tier 8 (1200 Science)
Technology
Prerequisites
Leads To
Effects
Economic Reform
Lateen Sail, Fiscal Policy
Military Prestige
Barding, Infantry Square, Cohorts
Industrial Progress
Chain Drive, Ballistics
