in which he demonstrated that we can alter what stimuli elicit a reflective response in canines.

研究中他用實驗在狗身上證明了，我們可以改變外在刺激來引出同樣的反射反應。

He showed this by sounding a bell just before he presented his group of dogs with meat powder.

實驗是這樣的，他先對一群狗搖鈴， 接著拿出肉粉。

After many presentations of the bell, followed by tasty meat powder, the dogs eventually began to salivate at just the sound of the bell.

在幾次搖鈴，接著拿出美味的肉粉後， 狗漸漸一聽到鈴聲就會流口水。

They salivated even when there was no meat powder present.

就算在沒有肉粉的情況下，牠們還是會流口水。

This phenomenon isn't limited to dogs.

這個現象並不侷限在狗身上。

Consider the placebo effect, in which a pill with no active substances brings about a response similar to a pill with a substance present.

想想「安慰劑效應」，也就是說一顆沒有任何療效的藥丸，給人帶來一種似乎有療效的感覺。

What changes here is our reaction to our ailment, such as perceiving less pain and not the ailment itself.

這裡改變的其實是我們對病痛的反應，像是感到疼痛減輕， 而不是疼痛真的減緩。

Or, consider the love humans have for a parent.

或是想一想人類對父母親的愛。

Some would argue that this love is instinctual, and they may be partially right.

有些人會主張這種愛是與生俱來的，而他們也有可能有部份是對的。

But, the argument fails to account for the equal amount of love that children adopted later in life hold for their adoptive parents.

然而，這論點沒辦法解釋當小孩被養父母扶養時，他們在往後的生活中對養父母為何也產生同樣的愛。

But the behaviorist argument can account for both accounts of love.

但是行為學家的論點可解釋這兩種愛。

A parent, biological or not, is constantly paired with things like food, smiles, toys, affection, games, protection, and entertainment.

父母親，不管有沒有血緣關係，會持續地和許多東西連結在一起， 比如食物、 笑容、 玩具、 關愛、 遊戲、 保護、 以及娛樂。

And a parent's constant association with these wonderful or crucial aspects of a child's life has a similar, albeit more complicated, effect that meat powder had on Pavlov's salivating dogs.

而父母親長期與這些小孩生命中美好或重要的事物連結， 儘管更加複雜，但這就像肉粉對巴夫洛夫流口水的狗的影響一樣。

In other words, if one's parent is predictive of really good or really important things, then one's parent becomes a really good and important thing, too.

換句話說，如果父母親能常常提供很棒或很重要的事物， 那麼父母親也就成了很棒及很重要的事物。

And there is also romantic advice to be gained from Pavlov's observations.

而從巴夫洛夫的觀察中，也可以得到一些浪漫的啟示。

We all need food to survive, right?

我們生存都需要食物，對吧？

And someone who can provide such things in a delicious, saliva-producing manner stands to become our human equivalent of a ringing bell.

而如果某人可以提供美味的食物，令人垂涎，那這人就扮演了相當於鈴聲的角色。

In other words, if you can cook one or more scrumptious meals for a potential love interest, there's a good chance that you'll be viewed more favorably in the future,

也就是說，如果你為你愛的人準備了美味的一餐， 那未來在對方眼中你可能會更令人喜愛，

even if you didn't prepare the delicious food.

即便下次你沒有準備美味的食物。

And who wouldn't want the love of their life drooling over them?

而誰不想得到一生摯愛的追求呢？

But life is not just bell rings and salivation.

但人生並不只是鈴聲和流口水。

There's also a dark side to this type of learning, called "taste aversion".

這類制約學習的過程中也有負面的效果，叫做「味覺厭惡」（譯註：又稱加薩效應。）

Taste aversion occurs when we ingest some food that eventually makes us sick, and, as a result, we avoid that food, sometimes for the rest of our lives.

當吃了讓我們生病的食物時，味覺厭惡會產生。最終，我們會避免吃這種食物， 有時甚至是一輩子。

Taste aversion is so powerful that the effect can be seen even if the illness is experienced hours later and even if the food itself did not actually make us sick.

味覺厭惡極具影響力，儘管是在幾小時後才感到不舒服， 或是那樣食物實際上並不是生病的原因， 我們還是能看到同樣的效果。

Such is the case when we have the flu, and, by accident, we ingest some food moments prior to vomiting.

好比說我們得了感冒，而意外地我們吃了某樣食物，之後吐了。

In this case, we know that the food did not cause the vomiting, but our bodies don't know that.

在這情況下，我們知道食物並沒有造成嘔吐， 但我們的身體並不知道。

And the next time we encounter that food, we are likely to refuse eating it.

而下次我們再遇到同樣的食物，我們很可能就會拒絕吃它。

Now, imagine the potential consequences of undercooking a meal on a first date.

現在，想像一下在第一次約會中，餐點沒煮熟所潛在的後果。

If the food makes your date sick, it is possible for them to associate that bad feeling with not just the food, but with your food in particular.

如果食物讓你的伴侶不舒服，對方很有可能把這個不好的感覺不單單與食物作連結， 而是特別和「你」的食物作連結。

If the episode was traumatizing enough, or if it also happens on a subsequent date, they may come to relate you with the consequences,

如果這插曲已經夠糟了，或是之後的約會也發生類似的事情， 對方也許把你和結果作連結，

just like Pavlov's dogs related the bell with the meat powder.

就像巴夫洛夫的狗一樣，把鈴聲和肉粉作連結。

In other words, the sight of you showing up at the next dinner date might actually make your date nauseous!

換句話說，在下次的晚餐約會時，你的出現很可能就會令她作嘔！

As the old saying goes, the fastest way to someone's heart is through their stomach, assuming you don't make them sick in the process.

俗話說：「要抓住一個人的心， 要先抓住他的胃。」當然前提是在這過程中，你沒有害對方生病。