Methods of acquiring Knowledge:
I)Non scientific method.
II) Scientific method.

I)Non-scientific methods: Under the non- scientific method there are five sources of evidence through researchers adopts:

I) The appeal to custom and tradition: The dependence on custom and tradition is to some extent a necessary human economy. As far as we refer to custom and tradition in the event of solving a problem.In many activities and situation this ready-reckoner serves the purpose very well. It largely determines our mode of living, mode of thinking, mode of tackling our problem mode of facing the situation and mode of making adjustments.The combined custom and tradition specify for us our food,clothes, speech, dealings etc. Ordinarily we obey the custom and tradition and avoid violating them.We try to seek explanation of the phenomena through the media of customs and traditions.

II) Appeal to authority: It central doctrine is that method of acquiring knowledge is authority of some kinds-the church, the state tradition of expert.The expert, in any field is the man,who has by some means or other, acquired enough prestige to be considered as authority, so it is accepted. One believes and his faith in it. The fact that earth was flat,was once believed universally and without question.A doctrine or institution that has survived for a long time can claim greater likelihood of being authority.Every human being used this method intelligently and legitimately.

III) Sensory Experience: Sense experience is the major method of acquiring knowledge which comes through senses. Modern science is empirical in methods. Concepts are formed as a result of sense experience. Knowledge comes, if sense organs work on favourable environment.The following methods can be applied to acquire knowledge through sense experience:

(i) Knowledge by doing: By using our sense organs, we do something and acquire the knowledge. As we touch the fire, we feel that it is hot .This knowledge becomes parmanent.It develops self-confidence in us. This method of acquiring knowledge is interesting.

(ii) Observation: While living in the society,the child observed the immediate surroundings as well as self. On the basis of observation,we gain experience and then tries to correlate these experiences with our life, society and nation.The facts of knowledge are elaborated in a logical manner. Naturalism believes in this method because it advocates that nature is the best source of knowledge.

(iv) Intuition: A possible method of acquiring knowledge is intuition.It is neither the result of conscious reasoning nor of the immediate sense perception. All knowledge have an element of intuition. It is merely the result of the accumulation of one’s past experience and thinking. It is a higher source of knowledge. Intuation May give us a clue to the vision of realiy, to receive the inspiration of imminent God or experience of unity with God.

(v) Tenacity: It is the willingness to accept an idea as valid knowledge because that idea has been accepted for a long period of time. Tenacity requires no evidence for a belief except that the belief is already accepted. For example, entering a religious place with the head covered and after removing the shoes, because it has always been like that.However, mere clinging to something does not ensure its truthfulness. Such customs may have been enforce in order to safeguard the interests of the erstwhile elites,and have since then continued. The meaning of belief goes on changing with time, place and conditions of existence. One cannot be flexible in choosing between one of the available alternative.

(vi) Personal experience: Man acquires knowledge through personal experience alse. For example,we learn from personal experience to grow perticular type of foodgrain or natural protection of plant from insects. A teacher, in the classroom may find that a particular method of teaching may be very successful with a certain group of pupils. Appealing to personal experience is a common and useful method of acquiring knowledge. When it is not use critically, however,it can lead to incorrect conclusions. A person may take errors when observing or when reporting that he has seen or done.For example, observation and records of what was experience or perform may be poorely made;generalisation may be drawn on insufficient evidence or too few examples ; incorrect conclusions may follow through prejudice ; and evidence may be left out because it was not consonant with earlier experience. Finally, there is always the danger of failing to recognize which were the salient features of the situation and which were irrelevant.

II) Scientific method: The scientific method is a process of systematically collecting and evaluating evidence to test ideas and answer questions. While scientists may use intuition, authority,rationalism, and empiricism to generate new ideas they donโ€™t stop there.

Scientists go a step further by using systematic empiricism to make careful observations under various controlled conditions in order to test their ideas and they use rationalism to arrive at valid conclusions. While the scientific method is the most likely of all of the methods to produce valid knowledge, like all methods of acquiring knowledge it also has its drawbacks. One major problem is that it is not always feasible to use the scientific method; this method can require considerable time and resources. Another problem with the scientific method is that it cannot be used to answer all questions. As described in the following section, the scientific method can only be used to address empirical questions. This book and your research methods course are designed to provide you with an in-depth examination of how psychologists use the scientific method to advance our understanding of human behavior and the mind.

References:
1) Philosophical, Sociological and Economic Bases of Education; Dr. Rainu Gupta; Tandon publications.

2) Methodology of Research in Education; Kulbir Singh Sidhu; Sterling Publishers (P) Ltd.

3) Gladwell, M. E. (2007). Blink: The power of thinking without thinking. How to think straight about psychology (9th ed.). New York: Little, Brown & Company.