A child prodigy, Pascal made essential additions to Descartes' work at the age of 16. By the age of 19, he had invented the world's first mechanical calculator. But despite his immense contributions to modern science and mathematical thinking, it is Pascal's wager with God that set him apart from his peers as a man fully engaged with both religious and scientific pursuits. One night in 1654, Pascal had a visit from God, a mystical experience that changed his life. Struggling to explain God's existence to others, he dared apply his mathematical work to religious faith. He argued for the existence of God basing his position on outcomes - his famous wager. By applying to the existence of God the same rules that governed the existence and position of the universe itself, Pascal sounded the death knell for medieval 'certainties' and paved the way for modern thinking.