The judgement of a goal  is depend on many factors, involved in its own value and capability.  I fundanmently agree with the speaker that the mean to obtain a goal is justifiable if it is worth.
  The satement of the speaker is tenable in some special circumstances such as the war. The following arguments demonstrate it to us. In the war to retrieve the dignity, Greek use the wooden horse cheated the Trojan and trun to be the winner in the end. This kind of behavior is acutally a cheat, but only by this way the Greek end the nine years war. To the extant that this kind of  mode is concerning the cheating, it is may seem reasonable when the way is applied in the war. Another apt illustration of this point involve the common situation which also in the battle between the countries.  In order to snoop the operation plan of the other country, some people will be assigned to be a spy in the hostile troop. This kind of way is nomal and general. People will take any means to win the war regardless of the morality and conscience.
  Whereas the speaker's assertion only apply to some particular situation. From the present situation as I see, the means by which people use to achieve the goal should be appropriate and not violate the criterion of the conduct. For the purpose to obtain the final result may bring severe influences. As everyone can get a high score through their effort or cheat, a student may use the auxiliary tool or his own knowledge to obtain a better grade, likewise, a athelet may creat the new record trough the tough training or exhilarant . The latter behavior will bring negative influence from various aspects.For an athelte, he cannot back to the stadium once the using of exhilarant is discovered. The team he belongs to will accept the suspectation from the outside, moreover the other member of his family will be also accused by people and the whole society will points to the reputation of the athlete. The worst infulence may lead image of a nation be ruined.
  Other means to achieve the goal like some extreme behavior also causea unhealthy effect. The notion can be proved from two arguments which relate to the education and selfprotection. There is a new word coming to people daily life, which refer to a kind of parents who help their children make every dicision and paved the future in order to let their children live a better life. This kind of conduct will bring nothing but the independent defiency of a person. It's  hardly to envision the consequence once their parents leave them alone. To be a normal social man independent is a crucial elements. The act of parents can be realise, unfortunately no bird can fly without wing, Parents just provide a enviroment which need not to fly but not a wing for a bird. The other argument has some thing with the outer space weaponization which some country advocate to develope weapon in the outer space in order to protect its own territory. Such behavior will bring a widely threat for the secuity to the other country since no country have ever assigned weapon in that area, which on the contrary will lead other country's imitation will bring the more jeopardy but not the secuity. One country's safety can be kept by the peaceful mean base on the healthy relationship between the other country. Head to head is not the best solution for a country's safety.
  In the fianl analysis, the notion that to fullfill a worthy goal use any means to achieve is justifiable may be only applied to some special circumstance. Thus, under the nomal situation we should consider the mean in a more suitable way which is my chief point.                  So much is new and complex today that looking back for an understanding of the past provides little guidance for living in the present. Under the rapid development of society, our world becomes totally different from the past. With the enhancement of life qualification plus the progress of technology, the present situation in every field has a big change compared to the old time. But I do not agree with the contention of the speaker that the understanding of the past provides little guidance for living in present. In today's new and complex situation, the chance is omnipresent, but at the same time the challenge exists everywhere. People have to confront the strange problem which is unable to find the reference from the past. With the process of globalization, many companies have to face the problem of popularizing product in a completely different country. When KFC firstly enter the China, the market situation is not so promising, the reference can barely find, however through the continuous exploration, KFC finally orient its direction on the Chinese taste and needs which help it become the champion in the fast food of China. Even though we can find the reference from the history, the directly copy is always seen an imprudent behavior. Take the 2009 financial crisis for example. The present government cannot copy the successful experience in 1929 for the different origin of problem besides the complicacy of society situation has supreme the past in a big scale. In that case the solution of the problem should focus on the current environment but not the history experience. On the other hand we should also see the point that even though the environment is not same, the essence is similarity. Consulting the history is to find those intrinsic unifications which has the significant meaning to the leadership. Despite the ever-changing world, the core of domination is the same----the inclines of the populace. From the history we can easily find those ruined regimes are all due to the violation of the populace will. No matter what kind of politic the government is, as long as it aims to service the populace, it will permanently exist. At the same time, the essence of people is never changed as well. The failure experience most stem from the inner lapse of people and the history provides us abundant information to consult such experiences which enacts a vital role to a human being. One of the basic functions of history is to let posterity learn the lesson from the mistake of their ancestor. The distinction of the south China tiger alarms the people indicating the greedy desire will bring the disastrous outcome to people. Meanwhile, those celebrated literatures as the necessary guidance instruct the life of people especially in the education field, the classical history story can never drop its position from the history stage. The story of Washington chopping down the cherry tree always as a paradigm to educate kids telling the truth which also continue today. People also never forget the confusion's word even in today, which tell people the philosophy of the life. Apart of it, the history is able to guide the target formulation for people. From the history, we can always find some darker phenomenon which is more or less reflects the deficiency of the construction of a society. Occupation, mind conservativeness, right abusing, realization the problem will help us build the more perfect system and policy to develop the progress of society. In the final conclusion, the past is not totally cannot guide today's activity. The new and complex of today indeed exist a big different to the old time. However the essence of idea and people is never change, the requirement of people vary a few. In that case, gasping the old experience with an effective harness will become the power of people today.