Related Clues:

• Cartesian connection
• Cogito __ sum
• Philosopher's 'so'
• Conclusion introducer
• Therefore, shifting sands in dessert leads to nothing
• There-fore
• Word of logic
• 'In which case ...'
• Therefore, to the old Romans
• As an end result
• Word before 'sum'
• As I'm showing you
• Logical connection hidden in eight puzzle answers
• 'By that logic ...'
• So, can this be added to make what you see out of the corner of your eye?