Bill O'Reilly's show is becoming a real snoozefest these days, which may be why I glazed over his discussion of religion with David Silverman of American Atheists earlier this week, which mostly entailed O'Reilly accusing atheists of "insulting" believers by running ads calling religion a "scam." Fortunately, Nicholas Graham at the HuffPo has more patience than I and happened to notice this little exchange:
O'REILLY: I'll tell you why [religion's] not a scam, in my opinion: tide goes in, tide goes out. Never a miscommunication. You can't explain that.
SILVERMAN: Tide goes in, tide goes out?
O'REILLY: See, the water, the tide comes in and it goes out, Mr. Silverman. It always comes in, and always goes out. You can't explain that.
Seriously? I mean, we knew that Bill O'Reilly was fond of pushing around his right-wing prejudices as conventional wisdom, and he's displayed ignorant buffoonery on many an occasion. But this is epic ignorance, the kind you really don't expect from a major TV news anchor. Hell, I bet even Glenn Beck knows that the tides are created by lunar cycles.
So, yes, Bill, we can explain that. Quite scientifically and quite precisely, in fact. From Wikipedia:
Tides are the rise and fall of sea levels caused by the combined effects of the gravitational forces exerted by the Moon and the Sun and the rotation of the Earth.
Most places in the ocean usually experience two high tides and two low tides each day (semidiurnal tide), but some locations experience only one high and one low tide each day (diurnal tide). The times and amplitude of the tides at the coast are influenced by the alignment of the Sun and Moon, by the pattern of tides in the deep ocean (see figure 4) and by the shape of the coastline and near-shore bathymetry.
Most coastal areas experience two high and two low tides per day. The gravitational effect of the Moon on the surface of the Earth is the same when it is directly overhead as when it is directly underfoot. The Moon orbits the Earth in the same direction the Earth rotates on its axis, so it takes slightly more than a day—about 24 hours and 50 minutes—for the Moon to return to the same location in the sky. During this time, it has passed overhead once and underfoot once, so in many places the period of strongest tidal forcing is 12 hours and 25 minutes. The high tides do not necessarily occur when the Moon is overhead or underfoot, but the period of the forcing still determines the time between high tides.
The Sun also exerts on the Earth a gravitational attraction which results in a (less powerful) secondary tidal effect. When the Earth, Moon and Sun are approximately aligned, these two tidal effects reinforce one another, resulting in higher highs and lower lows. This alignment occurs approximately twice a month (at the full moon and new moon). These recurring extreme tides are termed spring tides. Tides with the smallest range are termed neap tides (occurring around the first and last quarter moons).
We've known about this for some time, Bill. In fact, Isaac Newton famously first accurately described and predicted tides by lunar cycles in the Principia, published in 1687.
Next from O'Reilly: The calendar is proof that God exists and religion is not a scam. You can't explain why we have 365 days every year, can you?
