There are several arguments which are strongly supporting the psychological egoism which is the empirical doctrine that the determining motive of every voluntary action is a desire for one’s own welfare.
Firstly, the arguments which favor in psychological egoism argues that people are ego and selfish because people always act as what they desire to. This arguments state that people always act according to self-interest and every voluntary action are selfish. For example, a shopkeeper who is being honest and returned the changes that left by the customer after purchasing good is defined as an act which is ego and self interested because the shopkeeper knows that being honest will help the business and maintain the good name of the shop. Thus, psychological egoist said that people are acting what they want due to their desire and also self-interest, therefore, people are ego and selfish.
Besides, psychological egoist states that people are ego and selfish because they always act to get the pleasure and satisfactory. This argument indicates that every action of the people is aimed to get a good feel or being satisfied or in simple words, people acted to get the good feeling which may be gained after doing this action. For example, one who participates in the donation of blood do so due to the satisfactory and the good feeling which one may gained by donating his own blood. One might feel that he can help the people who need the blood and hence he feels satisfied by the action of donation of his own blood. Hence, this action which are acted to get the pleasure and satisfactory is pointed out by psychological egoist as the statement of people act are always ego.
Apart from that, one of the arguments in favor of psychological egoism indicates that people act is ego because they wanted to gain benefits from their action. This argument argues that people’s actions are done to get benefits such as fame, becomes popular, liked by others and so forth. For instance, from the perspective of the argument, a soldier who saved his comrade’s life acted bravely to get an award or a reward such as a medal. Arguments favor in psychological egoism also states that those who donates money to the poor, beggar or charity acting generous and donates money to the charities because they are enjoying the feedback from their action as they will get a good fame, becomes more popular and also being liked by the people due to their generous action.
As a conclusion, arguments for psychological egoism states that each of the human’s voluntary actions are being acted due to their desire to gain satisfactory, benefits and also because of their self-interest. Thus, these arguments agree the view of psychological egoism which states that people are ego because they are acting for their own good.
Arguments against Psychological Egoism
Many of the arguments oppose the theory of psychological egoism which states that human acts are selfish because people act according to their own desire. These arguments strongly disagree on the view of psychological egoism due to the consideration of several factors and using counter-evidence.
Firstly, the arguments against the psychological egoism states that human has genuine benevolence and genuine malevolence. This argument argues that human acts may be due to the capable of genuine benevolence and genuine malevolence which is the kind and the evil that planted in the human’s mind or spirit. For example, Mother Teresa who helped a lots of poor, sick, old and also children lent her hand to those needy because of her genuine benevolence, neither because of her own self-interest nor benefits. Hence, the opponents pointed out that the psychological egoism is false because there will be people who act voluntarily upon the genuine benevolence.
Besides, opponents of psychological egoism said that self-interest and interest in the welfare of others are not necessarily incompatible.  This argument states that people may be acting due to the completely self-interest and welfare of others. For instance, a business man never cheats his clients and customers because he knows that this action is good for businesses. From the point of view of the psychological egoism opponents, the business man does not cheat his clients and customers had take care the welfare of them and the business man did this for the good of his business which is the self-interest. The psychological egoism opponents hence state that people act not only for their self-interest but also may contain the interest in others’ welfare.
Apart from that, the argument against psychological egoism also states that human motives are oversimplified according to the psychological egoism. The opponents of psychological egoism state that one can has many motives when one is doing an action and only one of the motives may be the self-interest or benefits. For example, a father who gave his seat to an old lady on a bus may act so due to multiple reasons. From the perspective of opponents of psychological egoism, he may wanted to be the model to teach his son a lesson on giving a seat or lending a hand to the needy, he may wanted to get the satisfactory or good feeling after helping the old lady, he may also helped the old lady because of compassion and he may thought that it is dangerous for an old lady standing on a moving bus. Among the several reasons that are listed out, there are only one reason states that this father helped the old lady due to his self-interest. Thus, the opponents believe that human’s act is not solely due to the egoism but there might be other factors which are taken into the consideration before a human act.
As a conclusion, opponents of psychological egoism indicates that human acts are not solely because of self-interest nor benefits but can be causes by other factors such as the genuine benevolence, compatibility of self-interest and other’s welfare and also multiple of motives. These opponents believe that there will be some human actions which are acted against ego and truly out of a kind heart which is altruism as what have been done by Mother Teresa.