Although in real life we can see and experience suffering around us at any given time, we tend to easily forget what we have witnessed. As a result, the miseries we so witnessed cannot help us discern the true nature of samsara. This is why the Buddha taught us to regard samsara as nothing but suffering.

Some people may disagree and ask, “How can samsara be full of suffering when we have actually experienced happiness in this world?” But this feeling of happiness is really the result of us being obscured by some superficial and transitory appearances. Once we realize the truth behind the so-called happiness, we may begin to feel quite anxious about the precarious condition to which this life has been taking us so far.

- Quote from The Right View, "The Four Noble Truths—the Path Out of Samsara"

Therefore, we must strive to succeed in generating bodhicitta, no matter how difficult it is. The challenge is with our own self, with that selfish mind. It is a constant battle we must face with endurance.

As we breathe out during meditation, visualize our happiness and the causes of this happiness — the virtuous actions and merits of the past, present, and future — transformed into a white gaseous substance which is then dissolved into the minds and bodies of all sentient beings. Visualize all sentient beings receiving this happiness and its causes, and thus being free from suffering.

- Quote from Are You Ready For Happiness? Don't Let the Paper Tiger Scare You Off, "How to Face Happiness"

It is the motivation or the purpose for taking up a practice that really determines whether such practice is Mahayana or Theravada, mundane or supramundane.

- Quote from The Right View, "The Three Differences"

Before, lacking the essential wisdom, people tended to love themselves almost unscrupulously. But, under closer examination, selfishness is really without reason, groundless and moreover a big obstacle in our quest for ultimate happiness. This was never mentioned in anything that we learned from the secular world. Though some people might have said something similar, they lacked profundity. Only the Buddha told us the truth. Through his teachings, we are able to reflect on our previous actions and thus come to the conclusion that we were wrong being selfish. Henceforth, bodhicitta can be aroused. Among all the wholesome motivations, bodhicitta is the most precious and most significant.

When we encounter suffering, we can practice exchanging oneself for others; when we experience happiness, we can also practice exchanging the self for others.

From a mundane standpoint, we are enjoying our happiness when we have good health and material comfort; but from a liberation standpoint, we are wasting our blessings and happiness. In the sutras, the teachings remind us over and over again not to waste our happiness. Hence, when we are successful in our career or feel great joy in life, we must practice exchanging the self for others.

As we breathe out during meditation, visualize our happiness and the causes of this happiness — the virtuous actions and merits of the past, present, and future — transformed into a white gaseous substance which is then dissolved into the minds and bodies of all sentient beings. Visualize all sentient beings receiving this happiness and its causes, and thus being free from suffering.

- Quote from Are You Ready For Happiness? Don't Let the Paper Tiger Scare You Off, "How to Face Happiness"

Apparently, even non-Buddhist practitioners with some spiritual realization may still be confused about the workings of cause and effect, not to mention people without any right view or understanding. The complexity of the cycle of cause and effect and how it passes through the past, present and future make it possible only for the Buddha to comprehend entirely its causal relation. Others merely glimpse different parts of the cycle. These non-Buddhist practitioners are usually well learned; some may even have acquired certain clairvoyance over worldly matters. However, they jumped to a conclusion only based upon what they saw—virtuous people took rebirth in the lower realms—and from it the conclusion was drawn that cause and effect could not have existed. Then books were written and theories developed based on this conclusion, which gradually formed into a sect after attracting enough followers. This is how nihilistic view was established.

For example, is eating a meal counted as a good, evil, or neutral action? On the premise of not harming lives, eating itself is neither good nor evil. But as stated in the Abhidharma-kosha-shastra, if one wants to eat first in order to have the strength to kill, fight, or trick others afterwards, eating that meal is the same as committing evil. If the purpose of eating is to have energy to listen to a Dharma teaching, to liberate animals or to cultivate virtue, then this eating signifies a good action. Moreover, if these positive actions are invested with bodhicitta, eating can even become a Mahayana practice. On the other hand, when eating is without any specific purpose, not thinking of hurting or killing others, liberating or saving animals, it is neither good nor evil; it is, in Buddhist terminology, moral neutrality.

Naturally, before cultivating great compassion, one should generate renunciation first. One cannot have great compassion for sentient beings if one is unaware of the suffering of samsara, because compassion comes from the suffering of sentient beings. No compassion, no bodhicitta either.

- Quote from The Right View, "Buddhism—the Definition"