Friday, July 10, 2009

Logical Deductions

In the Milindapanha the question is asked as to why the sun's rays seem to shine more fiercely in the Winter than in the Summer, the opposite of what one would expect. The answer given suggests an ability to make accurate deductions from observing natural phenomena. The reason is, the text says, because Winter follows from the monsoon when rain the has washed all dust from the atmosphere. In the Summer by contrast, gusts of hot wind have filled the atmosphere with dust particles and these block the sun's rays (Mil.274).

6 comments:

David said...

Dear Bhante-

Although I am not particularly learned in this area, I believe it might have more to do with the angle of the sunlight. I understand that in the summer for any particular geographical area, the sun’s rays “come down” to earth more directly (close to perpendicular to the surface). In the winter, the rays strike at much more of an angle- closer to the horizon.

Perhaps what is being observed is that the sun in more likely to be in one’s eyes during the winter, than in the summer, as it appears lower in the horizon?

Respectfully, and very appreciative of the light you bestow on us with this wonderful blog.

Shravasti Dhammika said...

Mmm. That’s an interesting alternative. Are you sure that this phenomenon is the same in all geographical locations? The passage concerned was written in northern Pakistan/central Afghanistan.

David said...

Dear Bhante-

I grow less confident of everything with every passing day. : )

I did find this on the web about the change of seasons and the position of the perceived sun relative to the horizon:

http://csep10.phys.utk.edu/astr161/lect/time/seasons.html

Be well and take care.

no said...

In winter, the sun is not directly overhead even at noon. The further away from the equator is the country, the further away from the vertical will be the sun. Hence in winter the sun's rays have to pass through more of the atmosphere before they reach the earth, resulting in weaker sun rays.

Hence it is logical to expect the sun to shine less fiercely in winter, which is why it seems illogical that instead of being so, it appears to shine more fiercely. Thus the answer that the atmosphere was clearer during winter, in that particular location, appears to be a good answer.

David said...

No-

You might be correct- it could be due to some climatic influences. Clearly, it was not smog or manufactured pollution, but, I assume, it could be due to arid and wind blown sand conditions among others.

The issue might be what is meant by “shine more fiercely.” I do not believe it is referring to temperature, but to unwanted brightness. Often, we can tolerate the sun better when it appears overhead, than when it is in our eyes (especially without sunglasses).

As with most things, “cause and effect” are a certainty, but the determination of what particular cause precipitated a particular effect can be difficult to ascertain.

Best regards, wishes and prayers-

crosshairs said...

I would like to add my opinions on this issue.

Firstly, I would like ask, was this question valid in the first place? And by what measure? Did the subject use an instrument to reasonably claim that the rays were stronger?

Until these questions are answered, I shall refrain from providing further insights into this issue, insights that I have prepared. I'm going to cut a mango to share with my wife now so, till next time. I will be watching this section.