Sure. Even Isaac Newton had some crazy beliefs ("wrote more on Biblical hermeneutics and occult studies than on science and mathematics" according to wikipedia).
Sure, but Newton formulated Newton's laws, built the first reflective telescope, explained motion of planets, developed differential calculus, and wrote Principia.
Exactly. Newton is seen by many as the smartest scientist who ever lived. So I'm saying even those who contribute the most can have crazy ideas. It's typical. Not sure we disagree.
Or are you saying Kurzweil's contributions are very small in comparison?
He is remembered for his discoveries which were confirmed by hundreds of years of experimentation.
As a person he should be judged holistically, and that includes his affinity for the occult. If he were to be a professor of Stanford today, his beliefs on the supernatural should be taken into consideration and viewed as a lack of intellectual integrity(although with all that we know now versus what humanity knew during his time, his stance would most likely be different today).
Newton had boatloads of crazy beliefs and --oddly enough for his future reputation-- was probably kept from publishing most of his esoteric work by the religious intolerance of the period.
The Newton Project at University of Sussex and Cambridge University has collaborated with University of King's College in Halifax, Canada, and Indiana University to collect and transcribed his all of his writings. Their progress widget has them at 4,950,000 words so far.
But at this point he is probably doing more harm than good, for the reasons you describe.